Question

Using variable

Answer 1

Unfortunately you are completely wrong.

>“Given any number r, r2 ≠ -r”

This just tells you that r^(2) is not one specific number. It doesn't tell you, wether r^(2) is positive or negative. Infact your statement isn't even true in the first place as for example for r= -1, we have r^(2)= -r

Answer 2

Why did you put in -r. Why was there an r at all. If r = 5, you're saying 25 ≠ -5. Well yh, but this will happen to every number besides -1 and 0. If r = -1, you're saying 1≠1, which can't be true.

Instead of r^2 = -r, you could have r^2 = -m where m is a real positive number. but the problem with this is that it won't include 0. So the only way is to do r^2 ≥ 0